Corrosion behaviors of various steels and nickel-based alloys in liquid Sn media

Abstract

The purpose of the present study is to make clear the effect of material compositions on the corrosion behaviors in liquid tin (Sn). The corrosion tests of Fe, Fe-5Cr, 410 (Fe-12Cr), 430 (Fe-18Cr), 316L (Fe-17.3Cr-12.3Ni-2.2Mo-1.6Mn), Mo, Hastelloy C-276 (Ni-15.83Mo-15.67Cr-6.28Fe), Inconel 600 (Ni-15Cr-8Fe) and Inconel 625 (Ni-22Cr-9Mo-5Fe) were performed in liquid Sn at 773 K for 250 h. The Fe-Sn intermetallic compounds (IMCs) which were formed on the steels in liquid Sn were observed and analyzed by scanning electron microscope and energy-dispersive X-ray spectrometer. The thickness of the IMCs was thinner when Fe concentration of the steels was lower. The steels revealed smaller mass losses due to the corrosion when the Fe concentration of steels was lower. The dissolution ratio of Cr from the steels into liquid Sn was smaller than that of Fe. Hastelloy C276 corroded due to the dissolution of Ni and Cr in liquid Sn. However, Mo-rich layer was formed on the surface due to the dissolution of Ni and Cr into liquid Sn, and it mitigated the corrosion. Inconel 600 and Inconel 625 were severely corroded according to the formation of Ni3Sn4.

Keywords

• Corrosion
• Liquid tin
• Liquid divertor
• Steels
• Ni-based alloys
• Intermetallic compound